Are there any studies that show that shoulder relief girths actually work? I love the idea but I can’t seem to buy into the concept working.
Years ago I had a master saddler recommend using a wide straight girth. She reasoned that the wider the girth the broader the area of tension across the belly. If you were going to wear a tight belt a wider tight belt would be more comfortable than a narrow tight belt. That made sense to me.
She went on to suggest that if I felt I needed a shaped girth then to pick one with the widest narrow point I could find. Tension travels in a straight line/along the most efficient route. So physics does not allow the wide part of the girth to be carrying the direct tension and instead even though the girth mostly looks wide the main tension is mainly being carried through the girth at a width that is equivalent to its narrowest point. If the narrowest point is an inch or so then we are back to the skinny belt problem. Having seen plenty of old and well used shaped girths that seems about right too.
So I look at these shoulder relief girths and if I visualize them as a piece of fabric (or a string girth!) then pull on both ends I’m back to the problem of the reality being there is only a small width of girth that is the main thoroughfare for the tension. The integrity of the leather plays a roll–and if it were steel I could see it working better, but doesn’t the same pliability and flexibility that is necessary for a girth work in the first place work against the general concept of tension relief?
I love to hear some feed back from anyone that uses shoulder relief girths or any STEM folks out there that actually think about things like physics in real world applications…